Modern applications, such as wireless body area networks, wireless sensor network, wireless personal area network may require short range wireless communication devices (for example Bluetooth, Zigbee, Wibre) which may require low power and a flexible modulation module. Conventional amplitude shift keying (ASK) modulation method may meet the power consumption requirement but the performance may be easily degraded by nonlinearity of transmission channel and channel interference. Phase shift keying (PSK) modulation method may have a good immunity to channel nonlinearity but may have other issues.
Therefore, there is a need for an, alternative modulation circuit or method to provide modulation which may be relatively low-power and low-cost.